1/184 EU COMMISSION DIRECTORATE GENERAL FOR ENERGY AND TRANSPORT Study TEN-Energy Tunnel for the analysis of synergy between transport and energy sectors by high voltage transmission in rail-road tunnels in EU25 (including Bulgaria, Romania, Croatia) Final Report MVV Energie AG MVV-TA/4NT/0076114/000/01 Ed. 060531 2/184 Table of contents Page 0. Preamble...................................................................................................................... 5 1. Analysis of electricity cross-border countries congestions .......................................... 6 1.1. General methodology .................................................................................................................7 1.2. Electricity cross-border congestions ...........................................................................................7 1.2.1. Introduction .................................................................................................................7 1.2.2. Cross-border capacity auctions in central Europe .......................................................8 1.2.3. Detailed analysis of cross-border congestions ..........................................................10 1.2.4. Conclusion ................................................................................................................16 1.3. List of priority rail/road projects for synergy ..............................................................................18 1.3.1. Comments on the priority rail/road tunnels for synergy on electrical and civil works points of view ..................................................................................................23 1.4. Tunnel selection for a more detailed analysis ...........................................................................38 1.5. Multi-criteria analysis - Decision matrix.....................................................................................39 2. Feasibility study of installation of HV links in the tunnel ............................................ 42 2.1. Brenner tunnel ..........................................................................................................................42 2.1.1. General information on the tunnel .............................................................................43 2.1.2. Possible location in the tunnel- Type of link...............................................................47 2.1.3. Thermal behavior ......................................................................................................53 2.1.4. Power flow and short-circuit studies ..........................................................................53 2.1.5. Electromagnetic impact .............................................................................................53 2.1.6. GIL Gas Monitoring System ......................................................................................56 2.1.7. Highest compatibility of GIL with tunnel.....................................................................57 2.2. Lyon - Turin tunnel....................................................................................................................58 2.2.1. General information regarding this tunnel..................................................................59 2.2.2. Possible location in the tunnel - Type of link..............................................................70 2.2.3. Heat rise....................................................................................................................85 2.2.4. Electromagnetic impact .............................................................................................85 2.2.5. Electromagnetic effects .............................................................................................88 2.2.6. Connection to the grid - Tunnel exit on the Italian side ..............................................91 2.2.7. Connection to the grid - Tunnel exit on the French side ............................................95 2.3. Eurotunnel ................................................................................................................................97 2.3.1. General information on the tunnel .............................................................................98 MVV-TA/4NT/0076114/000/01 Ed. 060531 3/184 2.3.2. Particularity of a HV link between France and England ...........................................102 2.3.3. Possible location in the tunnel - Type of link............................................................106 2.4. Monte Ceneri tunnel ...............................................................................................................108 2.4.1. General information on the Monte Ceneri/Gotthard tunnels.....................................109 2.4.2. Zimmerberg - Gotthard - Ceneri base tunnels in the HV network ............................117 2.4.3. Situation of the work................................................................................................118 2.4.4. Type of tunnel and tunnel cross-section ..................................................................120 2.4.5. Type of link..............................................................................................................124 2.4.6. Conclusions.............................................................................................................127 2.5. Somport tunnel - Additional tunnel..........................................................................................128 2.5.1. Situation map ..........................................................................................................129 2.5.2. Present situation of the railway tunnel .....................................................................132 2.5.3. Cross-section of the railway tunnel..........................................................................134 2.5.4. Possible location in the tunnel - Type of link............................................................135 2.5.5. Magnetic field ..........................................................................................................138 3. Cables technology ................................................................................................... 139 3.1. Cable technology - AC (U = 400 kV).......................................................................................141 3.1.1. Cable technology.....................................................................................................141 3.1.2. Additional information - Insulation thickness............................................................149 3.1.3. Voltage....................................................................................................................149 3.1.4. Dimensions - size of the sections (for information) ..................................................149 3.1.5. Current development work and technological changes ...........................................150 3.2. Technology currently used in high-voltage cables for direct current - extruded synthetic insulation cable.......................................................................................................................151 3.2.1. State of the technology............................................................................................151 3.2.2. Main criteria for establishing the dimensions of DC cables......................................153 3.3. "GIL" (Gas Insulated Line) - technology..................................................................................156 3.3.1. Introduction .............................................................................................................156 3.3.2. Basic performance and main technical features ......................................................156 3.3.3. Manufacturing and factory routine testing................................................................161 3.3.4. Erection and testing on site .....................................................................................161 3.3.5. Earthing system.......................................................................................................162 3.3.6. Partitioning, monitoring, maintenance and repair ....................................................163 3.3.7. Leakage rate ...........................................................................................................164 3.4. Environmental impact in the event of AC/DC faults ................................................................165 3.4.1. Power cut times in the event of a fault.....................................................................165 3.4.2. Energy released at the area of the fault...................................................................165 3.5. Protection ...............................................................................................................................168 3.5.1. For AC - XLPE insulation.........................................................................................168 MVV-TA/4NT/0076114/000/01 Ed. 060531 4/184 3.5.2. For AC - GIL technology..........................................................................................168 3.5.3. For DC links ............................................................................................................168 3.6. Reliability of each type of links................................................................................................173 3.6.1. Reliability of the